Thousands of people have marched in Spain's capital to protest against a government plan to limit abortions

By Inmaculada Sanz

MADRID, Feb 1 (Reuters) - Thousands of people marched in Spain's capital on Saturday to protest against a government plan to limit abortions that has caused unusually open divisions in the ruling conservative People's Party.

Protesters from around the country joined the biggest demonstration so far against a draft bill to restrict abortion to cases of rape or severe danger to the mother's health.

Four years ago, Spain came in line with most of the rest of Europe when the then Socialist government legalised abortion on demand in the first 14 weeks of pregnancy.

"This is a step backward. We're going back 30 years," said Pilar Abad, 58, among the demonstrators waving purple signs who marched from the main train station to the national parliament.

Prime Minister Mariano Rajoy's cabinet approved the draft bill on abortion in December - in a move widely seen as an attempt to appease his party's disgruntled right wing - but it has not been submitted yet to parliament for debate.

Rajoy recently signalled he was open to modifying the proposal after critics from within the PP said he had failed to build party consensus for the bill and the changes would be out of step with public opinion.

Polls show 80 percent of Spaniards, including practicing Catholics, support abortion on demand.

BACKLASH IN THE PP

As Spain finally emerges from a prolonged slump, Rajoy has struggled to sell the good economic news amid the backlash over the abortion move.

The first voter opinion survey after the cabinet approved the draft bill showed the PP losing ground to the opposition Socialists, who have vowed to fight the changes to abortion law.

However, the PP has an absolute majority in parliament so once it agrees on the wording of the bill it will be able to pass it into law.

"A political party has to take into account what voters think. Voters have spoken through the opinion polls," Celia Villalobos, a People's Party MP who supports abortion on demand, told a group of foreign correspondents this week.

The PP is Spain's only significant conservative party and therefore always struggles to reconcile demands from the centre to the far right.

The more conservative wing has become frustrated with Rajoy over tax hikes to close a budget gap and over the release of prisoners from violent Basque separatist group ETA, under orders from a European court.

But the draft legislation failed to mollify the rightists and angered moderates. In a country where party discipline is strong, an unusual number of more centrist PP regional leaders and MPs have spoken out against it.

At the same time, the abortion reform failed to keep a disgruntled rightist faction of the party from splitting away in mid-January to form a new party named Vox.

At the PP's national convention being held this weekend in the northwestern city of Valladolid, abortion was barely mentioned in speeches by party leaders who called for unity.

On Saturday, speakers at the convention focused on the incipient economic recovery, the challenges of Europe's highest jobless rate and the threat presented by a growing separatist movement in the northeastern region of Catalonia.

But one notable absence from the convention was the party's veteran conservative ideologue, former Prime Minister Jose Maria Aznar, who has sharply criticised his former protege, Rajoy.

Aznar said he could not attend because he was travelling outside Spain. (Additional reporting by Sonya Dowsett; Writing by Fiona Ortiz; Editing by Sophie Hares)